Keep in mind, depending on the composition of the eruption, that dust that's escaping is actually powdered sugar sized particles of glass... Puts to shame any kind of Vandegraph generator we can make, but the principal is the same.
We have a Guyson cabinet at my work that uses fine ceramic media to blast parts clean or for finish reasons. The main media feed lines are unshielded plastic tubes. Get within 10cm of one on a dry day and you're gonna get some nasty surprises, and that's sand sized glass beads only blown by 60PSI air.